In some older sewage collection systems, for example as may found in the Eastern United States, Europe, and elsewhere, the sewage collection pipe or channel network was designed to collect sanitary sewage so that sewage transporting fecal matter and the like as well as intercept storm water is collected from streets, manholes and other sources. This storm water sometimes causes hydraulic flows to the sewage treatment plants in excess of their capacity to treat or dispose of the incoming fluid.
Some municipalities or pseudo-municipal districts have undertaken the expense of excavation and replacing these collection systems and separating the flows of sanitary sewage from storm water flows. However, this has substantial expense both in financial cost and inconvenience to the local population caused by the performance of such work. Accordingly, it is desirable to have some means to handle excess water flow systems having both sanitary waste and storm water.
There are devices now offered to intercept the larger solid material contained in such combined flows, while diverting the transporting liquid component of the flow. The liquid component will in general contain urine and finely divided solids. Still, it will be highly diluted by the storm water so that its environmental impact on a subsequent receiving body of water may be acceptable. These existing devices suffer from various problems such as vulnerability to jamming by tree branches or other large or bulky solids, blinding by solids due to relatively low cleaning water momentum, mechanical complexity and reliability issues, and operator maintenance intensity and risk exposure such as removal of net bags.
A similar and related problem exists where liquid from a body of surface water such as a river must be collected for subsequent use (i.e., a water treatment application or cooling water application as opposed to the above-described waste water application). It may be desirable to separate the trash from a quantity of the liquid without completely removing the trash from the liquid body.
Existing water intake screens used for the water treatment application suffer from difficulties similar to those for the preexisting solid intercept devices. Further, it may be difficult to meet governmental requirements regarding the subsequent disposal of the solids, i.e., trash, removed from the water.
Thus, it can be appreciated that a device solving the above-described problems would be a welcome advance in the art.